The statements herein only provide background information related to the present disclosure without necessarily constituting the prior art. TFT-LCD (Thin Film Transistor Liquid Crystal Display) has the advantages of low cost, low power consumption and high performance, and has been widely used in the fields such as electronics, digital products and so on. However, driving of the pixel units in the display panel needs to be implemented by using a gate drive circuit and a source drive circuit to drive corresponding scanning line and data line. With the improvement of the requirements of size, resolution, large view angle and image quality of the display panel, user experience is further improved, the cost is further saved, various manufacturers have developed a lot of manufacturing technologies related to the display field.
In the display panel, due to the influence of capacitive coupling effect, when the TFT (Thin Film Transistor) is closed and turned off, a voltage stability of data signal is influenced, and the image quality is further influenced; thus, it needs to perform a wave clipping on VGH (Voltage Gate High) of TFT so as to reduce a voltage difference between the VGH and VGL (Voltage Gate Low) of the TFT when the TFT is turned off, and to reduce the influence of the voltage of the data signal. For example, a resistance grounding discharge method is adopted to achieve the purpose of wave clipping, one end of a clipping resistance is connected with a power supply integrated circuit and the other end of the clipping resistance is grounded; the VGH generated by the power supply integrated circuit is discharged through the clipping resistance to form a clipped voltage waveform. The clipped voltage waveforms formed by the VGH are also the same for the clipping resistances having the same resistance value. Due to the fact that a clipped voltage waveform may influence pixel charging time and cause a horizontal block phenomenon (i.e., horizontal block is poor), for this reason, the clipped voltage waveform of the VGH needs to be controlled, so that the influence on pixel charging time is reduced and the horizontal block phenomenon is avoided; thus, clipping resistances need to be changed continuously in order to find an optimal resistance having the minimum influence on pixel charging time, this method needs many times of repetitive operation, is relatively tedious, and has a low working efficiency.